Flatting agent and composition containing the same



Patented June '20,- 1950 FLATTING AGENT ANDeCOMPOSI TION i CONTAINING TH'ETSAME Albert Saunders, l'ilaplewood nNe-lge assignorztto": Interchemical iC'orporation i N ew--Y01:k; N.; Y.", a-

corporation of Ohio No. Drawing: l Application-Jun'e-'-28, 1947';

- SerialNo. 757343 5 Claims. (01. 106-473) This invention relatestolnew fiatting agents particularly usefuliin the-lmattetcoating compo-1 sitions of the laquerand syntheticresin type. While many protective and decoratiyerfinishes are glossy, it is often desired to obtain finishes which are more or less matte and free from speed-l lar reflection, either for the decorative effect (as in furniture' finishes) or-forrthe utilitarian-reffe'ct (as':- in finishes for photographic: devices, w-h'erea non -reflecting surface is essential) Such anveffct can he :obtained by the use :of, veryihigh percentages ofpigment (e; g;.'. fiat/"await: paints; automobile undercoaters) i but it "is: often: de-: sirable to 1 get the same efiecir withoutv :loading the film with pigment either because thevfilm properties of a lightlypigmented finish are desinedhoribecause a transparent finish is desired. I To obtain this effect, the coating composition may be designed with an unbalancebetweenthe various film-forming ingredients and solvents; so that," on drying, a portion of the film is.:precip= itated'while the restof the'materialsare still in solution. A-: very satisfactorya-flattingeefieot may'rbe "obtained inthis fashion; Mandi-by careful compoundingrwithi certain classessof ingredients; exceedingly? tough; transparent-- dull-1 films are often ".1 obtainable. However: the gmethodr. is not applicable *to those :classes :of film-forming mas terials ,which :.cannot :be eprecipitatedrand' retain toughness of film. Eurthermore,-:.even-.with::the

coating compositions; and which can be dispersed therein to yield .films which are translucent .because of the similarity in :refractive index be tween the fiatting agents and'the-fiIm-forming solids, and are flat because of the zfact'thatytlae insoluble fiatting agents break up the light'hit ting thesurface of the film. The 'fiatting agents generally employed fall into two1classes'inor-" ganic transparent inerts; and-organic fiatting agents The common inerts are siliceous materials,:such

as infusorial earth, silica; silica-gel, some tales; etc.;. They are essentially pigments; capable of staying on'the surface of coatings while wet and during film formation, and which are transpar ent because-"their' refractive indices approach those rof :thesvehicles; and'i are. able to: produce eifeetivefiatting because of the-unevenisurface and; uneven light reflection so formed: They have-.three- 1 principal disadvantages. First; ,they are never perfectlytransparent when a'zfilmr of very: lowreflectivity is, wanted; Second, they settle verybadly tohard dry-cakes uponrstorage which :stir in ,with difficulty. This appears tobe 3e; propertyassociated with their particle size andtshape. Finally, the films,'producedeareeese sentially "pigmented: films, so: that whereehig-h flexibility is desired, aszin. artificial leathem the films are unsatisfactory because they craze on flexing.

The common organic 'flatting agents comprise certain transparent 'uncol'ored metal soaps (efg. magnesium; zinc; aluminum, and the- =alkaline earth metalsoaps of fatty acids); These "ma terials generally produce more transparentfilms than the inorganic fl'atting agents; since they are more nearly similarin' refractive index 1 to the film-forming agents. Because of their""similar-i ty in general constitutiom to the -vehicles, they stay in-suspension -better, and when they settle into flooculates theyare easily stirred back-unto uni-form dispersions.- Because of "these-advane tages they are preferred over the inert flats-vfor interior finishes "andfthe-like, However; these organic flatting agents have certain -marked "dis advantages; While they donotweaken a filmas badly as the inertssfilms containing these agents do" show 'crazing' when flexed, on; artificial leather, except in-the *case of :the' most soluble soaps, which are-' extremely difficult to handle: Certain of "the -soaps hydrolyze when the films containing them' are exposed to, water; causing an objectionable whitening ofthefilm; Also, the-' soaps are -all more 01'- less' soluble: in :h'ydroe carbon solvents,'- particularly: at elevated temper atures; thereby suffering loss :of flatness-a Gen erally, these flattingmaterialsmannovbe used in finishes designed tobadriedat elevated temperatures.

The known flatting agents of *the soapktype, cause-much less troublein oleoresinous "varnishes; wherethe solvents are-present -'in're1ativ'ely small proportion," and-"are largely'aliphatic hydrocar bons in characten'tlfam in lacquers and synthetic resin compositionspwhere:larger proportions of more powerful solvents are used.

There has recently'beon-developed anew type of 'fflatting' agent which" has reasonably good-re-f sistance to solution in the "solvents" of lacquer and synthetic 'resinyehicles; while "yielding tough films; These fi'atti'ng pigments are soaps: of

hardened rosin (e. g. maleated rosin, phenol resin modified rosin, and the like), preferably coated with an originally water-soluble lacquer insoluble vehicle such as methyl cellulose. These are described in Auer U. S. Patent No. 2,363,489.

I have discovered how to prepare a flattin agent having good non-crazing properties and good solvent resistance. Our method of preparation consists in preparing the magnesium, zinc, aluminum, or alkaline earth metal soaps of Manila gum. These soaps of the highly acidic Manila gum may be used as flatting agents alone, Or may be coated with an originally water-soluble lacquer-insoluble vehicle such as methyl cellulose, casein, or egg albumin, as is described in Auer, U. S. Patent No. 2,363,489. These substances, while acting to some extent as a binder for the pigment, also act to prevent solution of the pigment in organic solvents.

Manila gum, from which my novel flatting agents are prepared, is a naturally occurring high acid content resin, generally thought to con tain as high as 80% of the complex resinous mancophalolic acid. Being highly acidic in nature it is readily soluble in strong alkali such as potassium orsodi'um hydroxide to give solutions of the alkali metal salts of'the acid. These salt solutions are then reacted, under suitable conditions, with aqueous solutions of soluble aluminum, zinc, magnesium, or alkaline earth salts to precipitate the new fiatting agents of the present invention. Examples of our invention are:

Example I To 1216 grams of sodium hydroxide solution (containing 216 g. of sodium hydroxide) in a liter flask, was added 72 grams of Manila gum with stirring and careful heating. After addition of the -Manila gum was complete, the mixture was boiled for about 30 minutes to effect solution of the resin- The solution of the sodium salt was then added to an additional 1000 grams of water and this solution heated for 30 minutes at 100 F. with stirring, and a solution, containing 62.5 grams of aluminum sulphate dissolved in 270 grams of water and heated to 150 F., was added to'the sodium salt solution with constant stirring until the solution would turn blue litmus paper toa:slight pink color. The mixture was then heated to about 200 F. for about minutes with gentle stirring and filtered hot. The precipitate on thegfilter was washed with hot water until the filtrate from such washings was free from soluble sulfates when tested with'barium chloride solution'. Theresidue on the filter was then dried to constant weight in an oven at 160 F. and pulverized'. The'resulting pulverized pigment could be ground into nitrocellulose lacquers, synthetic resins, enamels and oleoresinous varnishes to give fiatting effects dependent upon the concentration of the 'flatting pigment used.

Example II The zinc soapof Manila gum was prepared according to the procedure of Example I by replacing the aluminum sulphate solution with a zinc sulphate solution containing 29.5 g. of zinc sulphate dissolved in 270 g. of water.

7 Example III 4 Ernample IV An aluminum soap of Manila gum was prepared as in Example I except that an aqueous solution of methyl cellulose (containing 7 grams of methyl cellulose in grams of water) was added to the boiled and cooled. (60 F.) sodium soap solution of Manila gum, and then the solution was precipitated with aluminum sulphate solution as in Example I. The precipitated product, consisted of pigment size particles of the aluminum soap of Manila gum coated with methyl cellulose and after filtering, washing, and drying was ready for incorporation in a coating composition.

Typical fiat pigment pastes, containing the pigments of the present invention, and suitable for incorporation in lacquers, resins, and oleoresinous varnishes are:

A. Nitrocellulose lacquers Parts by weight Flatting agent of Example I l5 5-6 sec. nitrocellulose (dry basis) 3 Petroleum naphtha (boiling point l65-l'75 C.) 49.2 Butyl acetate 16.4 Ethyl alcohol 16.4

Parts byweight 8 Flatting agent, of Example I 1 Xylol 69 Ethyl alcohol 9 Butyl alcohol 4 This composition, after thorough mixing in suitable grinding equipment, can be incorporated in various synthetic vehicles, such as, alkyd resins, alkyd-urea'resin, alkyd-melamine resin, urea resin, and melamine resin vehicles, to pro duce coatings having a dull or non-specular sheen when applied over surfaces for which the particular resin is designed.

C. oleoresinous varnishes I I Parts by weight Flatting agent of Example I '22 Mineral spirits 64 Alcohol 9.5 Butyl Alcohol 4.5

After grinding in suitable equipment to effect dispersion, the resulting paste can be incorporatedin oleoresinous vehicles for application on such surfaces as wood, metal, linoleum,,fabric, etc. The degree of flatness or dullness desired is. determined by the amount of fiatting agent in final formulation. 1

The above examples are illustrations of the difierent embodiments of the present invention and should not be consideredas limiting its scope.

I claim:

l. A product suitable for useas a. flatting agent comprising ,a metallic salt of a raw, non-. pyrolyzed resin, the particles of said salt being suihciently large that films formed from coating compositions containing said-particles will have a relatively. fiat surface, the metal being one from the group consisting of aluminum, magnesium,

calcium, strontium, barium and zinc, and said resin being a Manila gum.

2. A product suitable for use as a flatting agent comprising a metallic salt of a raw, nonpyrolyzed resin, the particles of said salt being sufficiently large that films formed from coating compositions containing said particles will have a relatively flat surface, the metal being one from the group consisting of aluminum, magnesium calcium, strontium, barium and zinc, and said resin being a. Manila gum, and said salt being coated with a film deposited from an aqueous solution of methyl cellulose.

3. A product suitable for use as a fiatting agent comprising the aluminum salt of a raw, non-pyrolyzed Manila gum, the particles of said salt being sufiiciently large that films formed from coating compositions containing said particles will have a relatively flat surface.

4. A coating composition which comprises a normally glossy drying non-aqueous organic film-forming vehicle, the films of which are dulled by the incorporation therein of a product comprising a metallic salt of a raw, non-pyrolyzed resin, the particles of said salt being sufficiently large that films formed from the said coating composition will have a relatively fiat surface, the metal being one from the group consisting of aluminum, magnesium, calcium, strontium, barium and zinc, and said resin being a Manila gum.

5. A coating composition which comprises a normally glossy drying non-aqueous organic film-forming vehicle, the films of which are dulled by the incorporation therein of a product comprising a metallic salt of a raw, non-pyrolyzed resin coated with a film deposited from an aqueous solution of methyl cellulose, the particles of said salt being sufliciently large that films formed from the said coating composition will have a relatively fiat surface, the metal being one from the group consisting of aluminium, magnesium, calcium, strontium, barium and zinc, and said resin being a Manila gum.

ALBERT SAUNDERS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,482,919 Ellis Feb. 5, 1924 2,075,025 Dietz Mar. 30, 1937 2,363,489 Auer Nov. 28, 1944 2,401,090 Masburn May 28, 1946 

1. A PRODUCT SUITABLE FOR USE AS A FLATTING AGENT COMPRISING A METALLIC SALT OF A RAW, NONPYROLYZED RESIN, THE PARTICLES OF SAID SALT BEING SUFFICIENTLY LARGE THAT FILMS FORMED FROM COATING COMPOSITIONS CONTAINING SAID PARTICLES WILL HAVE A RELATIVELY FLAT SURFACE, THE METAL BEING ONE FROM THE GROUP CONSISTING OF ALUMINUM, MAGNESIUM, CALCIUM, STRONTIUM, BARIUM AND ZINC, AND SAID RESIN BEING A MANILA GUM.
 2. A PRODUCT SUITABLE FOR USE AS A FLATTING AGENT COMPRISING A METALLIC SALT OF A RAW, NONPYROLYZED RESIN, THE PARTICLES OF SAID SALT BEING SUFFICIENTLY LARGE THAT FILMS FORMED FROM COATING COMPOSITIONS CONTAINING SAID PARTICLES WILL HAVE A RELATIVELY FLAT SURFACE, THE METAL BEING ONE FROM THE GROUP CONSISTING OF ALUMINUM, MAGNESIUM CALCIUM, STRONTIUM, BARIUM AND ZINC, AND SAID RESIN BEING A MANILA GUM, AND SAID SALT BEING COATED WITH A FILM DEPOSITED FROM AN AQUEOUS SOLUTION OF METHYL CELLULOSE. 